i have one question regarding NAS

im planning to buy buffalo Linkstation 4 bay NAS
and currently i want to fill only 1 HDD due to HDD price is quite high rite now
so if i use the NAS (with only 1 HDD) to store my files..can i add one more HDD later to RAID it even though the 1st HDD already has file inside ?

rite now i need space so planning to buy one HDD...later when price down will purchase more

help me on this...thanks in advance

thanks for the reply

im planning to do RAID 0 to boost the performance...but because of this problem i think i should go for JBOD instead...

but can you explain to me of JBOD performance compared to RAID 0 ? coz im planning to buy WD Green which is worst in performance but bargain in spaces/price